Overall, significantly more of the 1537 girls were overweight or obese than the 1629 boys.
More of the children whose parents were categorised as divorced were overweight or obese than those whose parents remained married.
They were 54 percent more likely to be overweight/obese.
"Children whose parents had never married had a similar prevalence of overweight and obesity to those with married parents," the study's authors noted.
The differences were generally larger for boys whose parents were divorced. They were 63 percent more likely to be generally overweight/obese than boys whose parents were married.
The same pattern was seen among girls, but the associations were less marked and, unlike the boys, not statistically significant.
Possible explanations for the link could include less time spent on domestic tasks such as cooking, an over-reliance on unhealthy foods and lower household income, the study concluded.
